Mystery submarine sighting gives clue to Russia's Arctic ambitions

A chance encounter by scientists adrift on an Arctic ice floe has given the first clues to a new Cold War being played out in in the far north, where Vladimir Putin has made no secret of his ambitions to extend Russian influence.

Yngve Kristoffersen and Audun Tholfsen, two Norwegian researchers, were coming to the end of their day when they spotted something unusual on the water.

"In the evening we spotted lights at a distance," the scientists recorded in their blog for October 16.

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